1. Technical Field
The disclosed embodiments relate to driving apparatuses; and particularly to a driving apparatus for driving a plurality of loads, such as light emitting diodes (LEDs) to emit light and a method for adjusting a drive voltage.
2. Description of Related Art
Light emitting diodes (LEDs) are widely used in various electronic devices, such as a backlight module of a liquid crystal display (LCD). A typical LED driving circuit includes several LED strings and several metal oxide semiconductor field effect transistors (MOSFETs) respectively connected to the LED strings, the LED string includes a number of LEDs connected in series. The LED strings are driven by a drive voltage from a voltage source, so that brightness of all the LED strings is the same.
However, in the manufacturing process, the resistance of each of the LEDs may be different. When the LEDs emit light, temperatures of the LEDs may vary, so that the resistance of each of the LEDs may also be different, resulting in different voltages across each of the LEDs. If the drive voltage is adjusted by decreasing it, some of the LED strings may not emit light. If the drive voltage is adjusted by increasing it, the MOSFETs may consume too much electric energy.
Therefore, there is room for improvement in the art.